Ossama Mohamed El-Tayeb

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A study was conducted to determine the role of inoculum size of a bacterium introduced into nonsterile lake water in the biodegradation of a synthetic chemical. The test species was a strain of Pseudomonas cepacia able to grow on and mineralize 10 ng to 30 micrograms of p-nitrophenol (PNP) per ml in salts solution. When introduced into water from Beebe Lake(More)
Fermentation media formulated from inexpensive locally available ingredients, namely soya meal, Proflo (a partially defatted cooked cottonseed fiour) and molasses, were assessed for growth, sporulation and δ-endotoxin production, by a mosquito-toxic strain of Bacillus thuringlensis H-14 locally isolated in Egypt, using an 8 I working volume fermenter. The(More)
We examined a total of 150 samples, including 27 eye shadows, 27 mascaras and 96 face creams, for their microbial contents. Mascaras were generally more contaminated than eye shadows. More than 75% of the examined eye shadows contained fewer than 100 c.f.u./g aerobic bacterial count compared to 63% of the mascaras examined. Viable bacteria were not(More)
Acinetobacter baumannii infections are compounded with a striking lack of treatment options. In many Gram-negative bacteria, secreted proteins play an important early role in avoiding host defences. Typically, these proteins are targeted to the external environment or into host cells using dedicated transport systems. Despite the fact that medically(More)
UV/TiO2/H2O2, UV/TiO2 and UV/H2O2 were compared as pre-treatment processes for the detoxification of mixtures of 4-chlorophenol (4CP), 2,4-dichlorophenol (DCP), 2,4,6-trichlorophenol (TCP) and pentachlorophenol (PCP) prior to their biological treatment. When each chlorophenol was initially supplied at 50 mg l(-1), UV/TiO2/H2O2 treatment supported the(More)
Fluoroquinolone resistance is gradually acquired through several mechanisms. In particular, chromosomal mutations in the genes encoding topoisomerases II and IV and increased expression of the multidrug efflux pump AcrAB-TolC are the most common mechanisms. In this study, multiplex polymerase chain reaction (PCR) protocols were designed for high-throughput(More)
Aureobasidium pullulans NRRL 6220 synthesized polysaccharide most actively in media containing sucrose, fructose or maltose with (NH4)2SO4 (0.6 g/l) or ammonium acetate giving greatest yields of the polysaccharide. With (NH4)2SO4 at ≥1.2 g/l, production of polysaccharide was decreased considerably. Polysaccharide production was highest with an initial pH of(More)
We examined a total of 192 samples, including eight different brands of shaving cream and eight brands of shampoo, for their total aerobic bacterial, coliforms and fungal counts. Shaving creams were more heavily contaminated with bacteria than shampoos. Viable bacterial were not recovered from 57% and 10% of shampoos and shaving creams, respectively. Only(More)
We examined a total of 54 samples, including 18 body lotions and 36 talcum powders, for their total aerobic bacterial, coliform and fungal counts. We also carried out anaerobic bacterial counts for talcum powder as well as tests to detect some potentially hazardous bacteria in all tested samples. Talcum powders were more heavily contaminated with bacteria(More)
Several medium ingredients locally available in Egypt were investigated for their ability to support δ-endotoxin production by two mosquito-toxic strains ofBacillus thuringiensis H-14 usingCulex pipiens for the bioassay of δ-endotoxin. Soya beans, black-eyed beans, common peas and lentils supported good production of toxin whereas peanuts, fodder yeast,(More)